AM3352: U-boot image for SPI flash

Ramesh Jain

Part Number: AM3352

Hello,

I have custom designed board based on AM3352, and boot option is set to boot from SPI flash.

I want to boot AM3352 with u-boot. I downloaded code of u-boot and compiled. it creates u-boot.bin, and u-boot-spl.bin file.

Can someone can explain me how to package this two images in flash? based on my understanding u-boot-spl.bin will go to address 0x0 of SPI flash, but how about u-boot.bin?

Also which file/function I should modify to take care of my DDR initiazlization and UART setup. I am using UART_0 in my design.

Thanks,

over 8 years ago

0 Dwarakesh Radhakrishnan over 8 years ago

Guru 13660 points

Hi Ramesh,

Which Software package are you using ?

0 Ramesh Jain over 8 years ago in reply to Dwarakesh Radhakrishnan

Prodigy 200 points

I am using uboot version 2017.03. from denx.
I have also downloaded SDK from TI website and able to compile, but that u-boot is old version and I wanted to use latest version as well as I want to learn so any help is really appreciated.

Thanks.
R.

0 Biser Gatchev-XID over 8 years ago in reply to Ramesh Jain

TI__Guru**** 393215 points

This forum supports only the TI released Linux SDK. The U-boot user guide can be found here: processors.wiki.ti.com/.../Linux_Core_U-Boot_User's_Guide

0 Dwarakesh Radhakrishnan over 8 years ago in reply to Ramesh Jain

Guru 13660 points

Hi,

For DDR config, please check the following folder : arch/arm/cpu/armv7/am33xx/

DEfault UART0 is set for console

0 Ramesh Jain over 8 years ago in reply to Biser Gatchev-XID

Prodigy 200 points

Hello Biser,
Thanks for your reply, I will focus on TI-SDK only. After compiling u-boot I got u-boot-spl.bin, u-boot.ibn, uboot.img.
Now my question is how these files should be placed in SPI flash?

At present I am not looking into rootfs or Linux kernel. I just want AM3352 to boot successfully with u-boot only.

based on my understanding
SPI_Flash_Image.bin (single file) will pack u-boot-spl.bin at address offset (0x0) and u0boot.img will go at address 0x040000

Could you please confirm?

-Dharmesh.

0 Dwarakesh Radhakrishnan over 8 years ago in reply to Ramesh Jain

Guru 13660 points

Hi,

CONFIG_SYS_SPI_U_BOOT_OFFS defines the location of u-boot. Basically the ROM code requires u-boot-spl.bin to be at 0x0. Remaining depends on what value CONFIG_SYS_SPI_U_BOOT_OFFS is being set. Please check its value in your codebase. In mine having processor-sdk version 03.03.00.04, it is following memory map:

/*
* Default to using SPI for environment, etc.
* 0x000000 - 0x020000 : SPL (128KiB)
* 0x020000 - 0x0A0000 : U-Boot (512KiB)
* 0x0A0000 - 0x0BFFFF : First copy of U-Boot Environment (128KiB)
* 0x0C0000 - 0x0DFFFF : Second copy of U-Boot Environment (128KiB)
* 0x0E0000 - 0x442000 : Linux Kernel
* 0x442000 - 0x800000 : Userland
*/

0 Ramesh Jain over 8 years ago in reply to Dwarakesh Radhakrishnan

Prodigy 200 points

Hello Dwarakesh,

This is what I was looking for, I will verify and update the status.

Thanks for sharing the info.

By the way one more question, in all these - where MLO and MLO.byteswap will fit? can I ignore that file?

Regards,

0 Dwarakesh Radhakrishnan over 8 years ago in reply to Ramesh Jain

Guru 13660 points

AFAIK, MLO is equivalent to u-boot-spl.bin and you can ignore it.

0 Ramesh Jain over 8 years ago in reply to Dwarakesh Radhakrishnan

Prodigy 200 points

Thanks D.warakesh, I checked MLO content - it is nothing but u-boot-spl.bin + some header at beginning.
I created image, and but unfortunately it didn't work. I still see "CCCCCC" on console, and that also comes sometime and than it stops.
I was in the impression that as per sysboot option - last option is UART and I will get CCCCC continuously at every 3 sec. till I don't transmit u-boot-spl.bin file with XMODEM protocol, and later I have to send u-boot.bin via YMODEM protocol.

I am not sure is there anything wrong with my hardware? I will check with my h/w team and update the ticket.

0 Dwarakesh Radhakrishnan over 8 years ago in reply to Ramesh Jain

Guru 13660 points

I was wrong about MLO.byteswap. Looks like it is used to flash into SPI. Please refer : processors.wiki.ti.com/.../Linux_Core_U-Boot_User's_Guide

0 Ramesh Jain over 8 years ago in reply to Dwarakesh Radhakrishnan

Prodigy 200 points

Thanks for the update. I also found one more reason for u-boot boot failuere. on my board MOSI, MISO got swapped for SPI-FLASH.

Normally DO - is used for MOSI and D1 - is used for MISO. But for during booting from reset - internal boot rom code uses D1 as MOSI and D0 as MISO.

I am working on board fix right now. and once I verifies I will update ticket.

By the way I really appreciate your help.

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AM3352: U-boot image for SPI flash